Conventional mechanisms for automatically dispensing fluids such as deodorants, disinfectants, insecticides and the like, use a number of different mechanisms. For example, in one device a synchronized motor is used to periodically operate an aerosol dispenser; in another, the movement generated by the withdrawal of a towel from a towel dispenser drives a fan to move air over a block of deodorant. In some arrangements door motion is used to operate mechanical drives that move air across a deodorant, while in others more sophisticated mechanical linkages are used, such as toggles and bellows, to actuate valves and aerosol devices. Those devices that are driven by the motion of a door were typically restricted to a fixed dispensing pattern; for example they dispense the fluid each time the door is opened and/or closed, which often results in too frequent or too infrequent dispensing of the fluid. Over-dispensing was undesirable, especially in the case where the fluid included pesticides, insecticides, and other harmful substances which were undesirable and could be injurious to the persons working in the area. More recently, a fluid dispenser which could be operated by door motion was disclosed, U.S. Pat. No. 4,030,638, using a cam member driven by an output shaft, typically an extension of a door closer. A cam follower actuator responsive to the cam member operates a fluid dispenser container such as an aerosol can to dispense the fluid at least once during each rotation of the cam member. In that design the cam member could be driven for only a portion of a full rotation upon each operation of the door closer unit and the cam could have one or a number of functional surfaces to operate the follower actuator to provide some flexibility in selecting the number of times dispensation would occur for determining the ratio of dispensations to door openings and closings. This approach too suffered some shortcomings; for example, it is difficult to easily, predictably adjust the ratio of dispensation to door closings, and the mechanism was relatively complex and expensive.